LED Headlight

[wagonman76]

Sorry I didn't mean to start a fiasco. Should have thought a little more, some parts far south and without as much nearby water would probably see 90F more often. Almost never see it up here.

All I meant by warm is the outside air temp was 20F, and the air around them felt a bit more than that. But still cold compared to the human body temp. If the air around the LEDs was 40F I would be able to feel the difference even though it was technically cold compared to the human body temp. Instead of warm I should have said not as cold. Only way to figure out what will give the best output without heating up considerably would be to experiment anyway.

The reason I wanted to stay with 3 LEDs per resistor is for the control. I could still bump up the resistor size to get around 5ma or whatever I need to keep them cool. I just want them to be able to handle normal voltage fluctuations.

Say I go with 4 LEDs per resistor. To get 5ma at 13.5v I would need a 60 ohm resistor. Let that voltage fluctuate to 14.5v and I would be at 22ma, enough to fry them in little time.

Now say I go with 3 LEDs per resistor. To get 5ma at 13.5v I would need a 720 ohm resistor. Let that voltage fluctuate to 14.5v and I would be at 6ma, hardly a change at all.

When I tried them outside I was seeing how the cutoff worked. There was a definite cutoff from the blinding zone. The LEDs I think would be most comparable to HIDs, and wiki says HIDs need to be aimed for a sharp cutoff from the blinding zone. I also do plan to try them behind a normal headlight lens for a diffusion effect, as well as stock outside appearance.

[winkosmosis]

Originally Posted by Christ

You have extreme faith in people knowing the difference between efficiency and novelty, sir.

How many people do you think buy them out of impulse solely? How about the ones that are looking for any excuse to show how "green" they are? (I use green in this case in quotes to emphasize that they're only pretending, and in reality, know nothing of the lifestyle which they tout.)

Frankly, if people had a little more fiscal sense, things like this wouldn't be an issue to begin with.

LEDs have a big advantage over CFLs. No mercury

[Christ]

Originally Posted by winkosmosis

LEDs have a big advantage over CFLs. No mercury

That's cool and all, but I wasn't arguing for CFL's, I was arguing against the high price of LED's and the fact that some people will pay it for the novelty of owning a piece of "green" "technology".

(Comment about fiscal sense.)

[EcoBill]

wow nice write up, I plan on doing this on my taillights/turn signals

[ddhaire]

It's nice to see someone playing around with LEDs. It's a shame that the big guys aren't doing it so that the price could be brought down. I feel that LEDs are the way to go with all lighting.

[endurance]

Anyone else here watch Storm Chasers? I noticed that the TIV2 has LED headlights. Unusual design. I wonder how effective they are in that configuration? The real challenge would be building them inside an aimable unit that had proper dispersion so you didn't blind oncoming drivers, but still had light reaching the right regions of your field of vision down the road.

[Nerys]

The biggest reason the manufac's don't make more of them is that "done right" they will outlive you and that means a LOT LESS PROFIT unless they can make them really expensive REALLY BRIGHT (per element to shorten the lifespan) etc..

[ami8i]

Hello captainslug,
have you replaced your flash lights with LEDs?
In post #9 I read that it's not so easy to do, but couldn't read any resulsts in later posts.
I have to design a flash system for a high efiiciency velo mobile Velomobile - Wikipedia, the free encyclopedia and still look for the best LEDs to do this and the right number so that is compareabele to common 21W bulb flashers.


@your head light:
I wonder that you have no narrow beam which does not annoy oncoming traffic. unfortunality some bicycle LED light homebrewers do it similar, so I draw a figure to show the waste of light e6-schnitt_xr-e_relIntensitaet_Polarkoordinaten | Flickr - Photo Sharing! becasue a siginifant part is lost at heaven (even if the light is pusehd down).
My latest finished LED light projekt (hub generator powered) is a half cutted aftermarket fog car reflector with Cree MC-E Flickr: ami8break1's stuff tagged with diyledscheinwerfer5 I paid attention to get most light focused out of the reflector (=high efficiency).
Another LED guy started an interesting (batteries powered ) project with Aftermarket scooter Ellipsoid head lights, I guess this could be a good starting point Es werde Licht!!

Horst

[RegularPete]

Excellent guide, very detailed!

[ccryder]

Take some hints from the LED flashlight forums for focus, spread and throw. You will not have the DOT beam pattern but, yo could have something workable.

I have gone with HID kits for the past 11 years and they have improved greatly (yes I have read what Daniel Stern has written).

My 11 Fiesta has HID low beams which draw 1/2 what the coventional bulbs would draw and Silverstar high beams. I can see halfway to..................... well yo get the point. Places like DDM-tuning.com have great prices and great hardware with very good service.

Time2Roll
Neil S.